This conical hill is among many hummocks found at the NE base of Jocotitlán volcano and represents part of the edifice that collapsed in a massive volcanic debris avalanche about 9,700 years ago. The hummocks contain abundant large blocks (1-10 m in diameter) and larger mega-blocks (10-20 m in diameter). The largest are up to 200 m high and occur within 3-5 km of the volcano along with large parallel transverse ridges up to 2.7 km long. The size and height decrease towards the margins of the deposit.

Photo by José Macías, 1997 (Universidad Nacional Autónoma de México).

This image is made available under the Creative Commons BY-NC 4.0 license terms.

Keywords: hummock | debris avalanche deposit

Jocotitlán